


Know Yourself and Stay Strong

by Cheriiu



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Angst, F/M, I had this idea for a while so I'm gonna make it happen, Slight crossover??, Violence, and sorry there's not much claudeleth but I promise I'll try to write more fluff soon, don't pretend to be a beloved professor, lesson to be learned
Language: English
Status: Completed
Published: 2019-11-14
Updated: 2019-11-14
Packaged: 2021-01-30 06:02:49
Rating: General Audiences
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 1
Words: 2,802
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21423367
Author URL: https://archiveofourown.org/users/Cheriiu/pseuds/Cheriiu
Summary: This is the first time she's hearing this. Lady Rhea hasn't said anything about this and if she hasn't said anything then Seteth must have been holding back as well. Knights disappearing without a hint of them possibly running away? She's dealt with this of event at Garreg Mach already that's for sure, Flayn's rescue was enough already but Shamir is pushing her to help with another.
Relationships: My Unit | Byleth/Claude von Riegan
Comments: 2
Kudos: 12





	Know Yourself and Stay Strong

Byleth was a bit puzzled by this request.

"I need you and your class to help me with some scouting."

Shamir came up to her in the dining hall while she was waiting in line for this week's lunch special but apparently from the mercenary's tone, it looks like she won't be indulging in it for today. 

"Why do you need us to help you with recon? Don't you normally do this alone?" Byleth asked as she set down her tray to cross her arms.

Shamir sighed heavily "Yes, and I was opposed to it at first but Seteth informed me that I should take backup because apparently safety in numbers is needed for this mission of mine. We lost a few knights for the past few weeks and an investigation is in order."

Byleth furrowed her brows at that last sentence. 

"Some of the Knights of Seiros haven't reported back from their own reconnaissance just last moon. None of their family members are aware of why they disappeared and are insisting they had no motives to run away. They getting increasingly worried. If you're not comfortable with this then I'll be taking my leave now Professor." 

This is the first time she's hearing this. Lady Rhea hasn't said anything about this and if she hasn't said anything then Seteth must have been holding back as well. Knights disappearing without a hint of them possibly running away? She's dealt with this of event at Garreg Mach already that's for sure, Flayn's rescue was enough already but Shamir is pushing her to help with another. 

"I'll go with you. Just give me a bit of time to gather my students and I'll meet you at the entrance."

Shamir gave a small smirk and nodded. "Good don't take too long."

✦✧✦✧

"Hmph...Professor I'm gonna leave temporarily to do another round and if I come up short again then you and your class are dismissed."

Byleth nodded as she watched the mercenary leave through a thicket of forestry until her form was gone from sight. They all spent a good hour searching but haven't found any evidence linked to the missing knights which frustrated most of her students. 

"Ugh...this is so boring! I can't believe we haven't found anything and my new skirt got ripped up too!" Hilda whined as she inspected said skirt and her lip quivered at the small tear it sported. 

Claude chuckled and was quick to make a comment "I didn't know it was such a crime Hilda! A cut like that...how devastating!" 

The pink haired girl rolled her eyes and was arguing back and forth with the House leader as Byleth lost her train of thought. Ignatz and Lysithea were sitting on a nearby rock together to let their sore feet rest, Lorenz had suddenly joined in on the discussion in agreement with Hilda that proper clothes were adequately needed to maintain a noble image, Raphael was munching away on some beef jerky he brought for emergencies such as this apparently and Leonie was testing her bowstring as she had nothing else to do in the meantime. 

Suddenly from the corner of her eye, she spotted something move. It was quick but she caught a glimpse of a human figure moving quickly into the Sealed Forest. This made Sothis speak up.

_"My, my...looks like you've found what you were looking for after all."_

_"It could have been Shamir."_

_"Oh come now we both know that's not her. Leaving and then suddenly coming back only to run away without saying a word? As a distant shadow no less? That hardly makes any sense at all!"_

_"I suppose that's true."_

_"Right? Now quickly! Before they get away!"_

Byleth gave a slight nod as she unsheathed her sword and abruptly left to follow the unknown person. 

Claude was the first to catch the sight of this and rallied everyone's attention to follow.

✦✧✦✧

The figure was starting to become less and less as a shadow the more Byleth closed in, her students lacking behind as they were not quick enough to catch up just yet. She noticed some things about them that were oddly...familiar.

They have shoulder length hair, and were sporting a flowing cape of some sort. Not only that they looked to be about the same height as herself and she caught the glimpse of a sword strapped to their side.

_"They seem to bare some similarities to yourself...such a thing cannot be a coincidence."_

Byleth agreed and soon their chase came to an end. They seem to be at the very edge of the forest and the being was standing in front of a large cave entrance as if they were intentionally leading her here.

They turned to Byleth and she was shocked to see what was revealed in front of her. 

The figure looked exactly like Byleth somehow. Her earlier observations about their hair, cape, height and sword were correct and she can clearly see some other disturbing details as well. They have the exact same hair color, clothing, blank stare as her and somehow they're wielding a SECOND Sword of the Creator. All of this was enough to send a chill down Byleth's spine. 

They said nothing to her and when she was about to intimidate them when the Golden Deer have finally caught up with her.

"Hey Teach! It's not good to make us run after---" 

Whatever Claude was about to say was lost as he and the other fawns took in the sight of the second professor ahead.

"Whoa that's really creepy!" Hilda said taking a step back.

"I've...never seen anything like this before in real life." Ignatz adjusted his glasses.

The others were too shocked to say anything and were just staring wide eyed with mouths in the shape of Os. Marianne was hiding behind Raphael's large figure praying quietly.

Shaking off his stupor, Claude walked up and tried to put on a convincing enough smile for the other Byleth as he spoke "Hey there uh...Teach #2! Funny running into you here! Must be faith that I sorta meet you in the same way I met Teach #1 huh?" He said putting a hand on the original's shoulder. 

"So do you mind if bend your ear a bit as to what exactly is going on here?" 

The second Byleth said nothing. They blinked once before quickly making their way inside the dark cave behind them.

"Rude;" Claude shakes his head, his hand still gripping onto Byleth's shoulder as he turns his head to look at her "Looks like Teach #2 wants us to follow them but I'm guessing what we're about to see if we go in is the reason why the knights are missing in the first place."

He was right. Byleth knows it judging from the treacherous feeling that's still left in the air. But even so...they came here to find any shred of evidence and so far a duplicate Byleth leading them into a dark unknowable cave is the best they got. She knows her students are capable of taking a chance into the unknowable so now is a good time as any to do it again. 

"We need to complete our mission so everyone ready yourselves and prepare to move forward."

✦✧✦✧

Like any typical dark spooky cave; it was moist, unlit and most of all deep. It was a good thing Byleth had stocked up on torches before they left as her and Claude held up two in front of their group. Everyone stuck close together as they followed their professor and house leader.

So far the cave was just one way, going in deeper and deeper as they kept an eye on the other Byleth. Always stopping for a moment's notice before sprinting off to lead the Golden Deer down further.

Suddenly Byleth's boot hit something metallic and looked down to see a familiar looking helmet laying in front of her.

Claude noticed her gaze and crouched down to pick it up with one hand to inspect it "Looks like the Knights of Seiros took the same detour as us Teach." He said as he twisted it around.

Hilda shivered "OK that just screams bad news and I think it's best we go back right now yeah?" 

"No way, we've made it this far and we can't back out now. This will reflect badly on us and I know Captain Jeralt would never run away from something like this." Leonie said with a look of determination. 

Lorenz nodded in agreement "Very true Leonie. Cowardice is no longer optional now that we know there's a positive threat that will endanger the commonfolk and as a noble---"

"OK, OK I get the point." Hilda sighed heavily, ignoring Lorenz's annoyance for being interrupted. 

They kept going and along the way the saw more bits and pieces of armor that was left behind by the knights. Not only that; some discarded bones, broken weapons and other material possessions were left behind most likely due to an ambush. 

"Professor! I think I see some light up ahead!" Ignatz exclaimed and it was true. There was a faint glow in the distance and just as they were closing in.

Something erupted and trapped them from behind. 

Lysithea and Marianne yelped and everyone turned around to see some odd looking roots restricting them from going back. Raphael tried to pull them apart but to no avail, even the combined magic of Lysithea, Marianne and Lorenz wasn't enough. Soon more roots started sprouting up from behind as they continued forward, ensuring that there was no other way. 

The other Byleth ran ahead and the Golden Deer were welcomed to a bunch of hanging corpses of animals AND humans alike inside. Some were hanging from their necks with lifeless eyes and partially mutilated bodies, while others seem to have no heads at all with their bodies either dangling from the waist or a single leg. 

"Holy shit Teach...this is FAR from what I had in mind." Claude said as his gaze went from one corpse to the other. 

Byleth's focus was only on her double and the moment she jumped up onto the platform they no...IT was standing on, a loud shriek resonated that had everyone cover their ears.

Then its neck snapped and twisted around gruesomely.

Everyone stood there as they witnessed the creature change, its imitation of Byleth slowly losing its lower body and was being replaced by a pitch black spine that leads into a orange pulsating belly. Long spider like legs jutted out from its sides that made even Leonie recoil in fear. Sickening cracks continued on until finally the transformation was complete.

What stood in front of them was a horrifying, diseased looking spider creature with the appearance of the Golden Deers' beloved professor contorted upside down from the waist with soulless, lifeless eyes as if death itself was peering out through them. 

"Everyone move now!" Claude yelled when the creature stood on its back legs to let out another piercing screech. 

It charged foward 'Byleth's' arms dangling as it tried to squash some of them with its large being. Everyone got out their weapons and tried to get some hits in, only for it to jump around erratically to stomp on them.

"Leonie, Ignatz, Claude! Use your arrows to try and shoot it when it's in the air!" Byleth commanded as she barely just dodged another incoming charge. 

All three of them notched their arrows as they tried their best to shoot at the beast. However Ignatz was the most hesitant as if shooting something that had somewhat the appearance of his dear professor was too much for him. This proved to be his undoing as the monster crushed him under its weight with his sharp limbs impaled directly into his eyes and abdomen. 

Terrified screams came just as Byleth used the Divine Pulse. This time Byleth rushed over to Ignatz's side and commanded the Sword of the Creator to transform into a whip to lash out at the incoming creature. It was enough force to send it barreling back and have Leonie and Claude shoot a couple of arrows at its grotesque belly. It gave out another piercing cry and soon it jumped high enough to be covered by the misty ceiling.

The skittering can be heard above as giant globs of orange puss of some kind rained down on them. Everyone had to scramble to not get hit for the globs that hit the ground were sizzling and dissolving like acid. 

Lorenz sent out multiple Fire spells in attempt to hit it while its not on ground level with them. But he was a second too late when the puss dropped onto his face and he was letting out a painful scream as it was melting his face. 

Once again Byleth had to use the Divine Pulse and rewind time to the point were she yelled at Lorenz to move out of the way. This time the glob dropped onto the floor bubbling away as Lorenz lets out a mortified sound from almost being hit. 

The monster dropped down in the center and let out another scream as it erupted like a volcano to try and splash everyone with his acidic fluids instead. 

Some dots of it did get on their clothes (much to Hilda's horror when it ruined her skirt further) but it wasn't enough to dissolve into their flesh. After that it went back to jumping and charging.

Claude was standing next to Byleth breathing heavily as he tried access what to do next "Teach #2 has a lot of tricks up its sleeve;" He shot another arrow that hit it in the neck "But I got a couple of my own if you're up for it?" 

That scheming grin usually unsettled Byleth but right now it was that of an angel and she nodded in agreement.

"Raphael when it comes at you grab it by the head!" Claude yelled.

The muscled blonde gave a thumbs up as he stood his ground with arms outstretched as if he was about to wrestle a bull. In some weird way he was. 

The creature charged forward, taking the bait and soon Raphael grabbed onto it by the head (or in this case the upper half of 'Byleth') grunting and straining his muscles as it tried to push him back.

"Lysithea hurry and use Dark Spikes T!" Byleth called and the mage muttered the incantation and soon large shadowy spikes appeared and punctured its main body. 

The cry it let out was loud enough to shake the foundations and give everyone a headache. It whipped its head ahead and flung Raphael into the wall that made Marianne rush over to help him. 

It turned around and with the last of its energy, leaped up and attempted to crush the real Byleth only for Claude to stand in front of her and let loose another arrow.

"My moment has arrived!" 

The arrow shot right through it's head (right between 'Byleth's" eyes) and it fell backwards and let out one final scream until it started shaking uncontrollably as if it was about to explode.

"Hit the deck everyone!" 

The Golden Deer hid behind rocks and backed away far enough for the monster to violently burst into a gooey, disgusting mess with the 'Sword of the Creator' clanking onto the ground like useless metal.

It was over and just like that the strange roots that were blocking the way back retreated.

Byleth was staring at Claude with wide eyes as she watched him steady his breath before letting out a sigh of relief. He turned his head and gave her a tired smile "Guess we outta report back to Shamir huh?" 

She was speechless but she managed to nod in agreement. It's not the first time Claude saved her life but when he does, it always leave Byleth feeling proud and warm inside. He really was becoming a fine leader and fighter now. 

Once everyone gathered their bearings, Claude managed to find that the creature was hiding some Umbral Steel further in. Both him and Byleth decided to keep it, just in case the Sword of the Creator or other Heroes' Relics needed refinement in the future. Everyone hurried as they set off to leave this horrid place before something else strange comes up.

They exited the cave just in time to find a scowling Shamir in front of them.

"Professor, Claude do you have any idea how stupid it was to leave without informing me first? What in Fódlan were you even doing?" 

They both looked at each other before Claude let out an embarrassed chuckle.

"You might wanna sit down to hear this Shamir."

**Author's Note:**

> When I first saw Nosk pretending to be the Knight I'm like "Oh fuck what's happening??"  
This little shit became one of my fav bosses in Hollow Knight so I hope you enjoy this small development in Claude and Byleth's relationship  
Through the power of killing a crossover monster XDD


End file.
